Diff output from a rewrite of a function

Hi,

I have a C source file in which couple of functions are fully rewritten (only a part of the file), almost no real similarities (block closing parents will obviously match still and couple of other keyword lines here and there). I wonder if there is way to produce diff that does not get confused by the empty lines / identical lines that are present in both original and the modified version. Default diff output is very bad looking (IMHO) because these identical lines cause a "synchronization point" to occur, that is, each identical line of the original is not considered as +/- but left as is. Thus I have something like 3-6 add+del blocks per function with a part of the change rather than e.g., one block per function or so... I found -B from man git-diff-files, but I guess "complete rewrite changes" means whole files as it did do anything.

Any ideas?

I'm currently using 1.4.2, if that's significant.